Sacramento daily record-union. [volume] (Sacramento [Calif.]) 1875-1891, 1887-09-10

THE KEYSTONE CONSOLIDATED
Is situated at the southeast end of the town
of Amador, about two miles northwesterly
from Sutter creek, in the Amador Mining
District, and has an altitude of 1000 feet
above sea level The consolidation in
cludes Spring Hill, Geneva and Garfield
claims The location was made in 1850
and has been worked almost continuously
The eastern, or hanging WALL is a meta
morphic rock, called by the miners green
stone, but SO far the foot or western wall is
not well defined. Lying against and on
the west side of the greensboro is large
vein of low grade quartz thence westerly
there are from 200 to 800 feet of argilla-
ceous slate in which the best ore deposits
occur, thence an admixture of slate and
spar in which ore does not exist. The
average width of the zone is about 400
feet; the course of the vein is northwest
erly and southeasterly. The hanging-wall
dips easterly at an angle from 450 to 60o at
the surface, and 450 at the bottom length
of the shoot is 800 feet. There are two
shafts north and south the north shaft,
used for hoisting the ore from the mine, is
1905 feet on the incline Of 49o, reaching
vertical depth of 1000 feet; the south
shaft, used exclusively for pumping out the
water is l, I25 feet on an incline of from
450 to so, with vertical depth of $50
feet. The nature of the ores is free mill
ing, carrying from one and One-half to one
and three-quarters per cent. of auriterous
sulphurets. The method of reductions is
crushing by stamps, and of recovery is
amalgamating in the battery and collecting
on copper plates on the outside.
On the east side of the contact is large,
poor vein of quartz, varying in thickness
from , feet to 10 feet, which is very spot
ted 200 feet west from the greensboro, III
the argillaceouS states, occur the next de-
posits, which are irregular and confined to
Il northwest and southeast channel; these
deposits are from feet to 80 feet thick,
and better quality of ore than that found
on the east side The west channel is
from 800 to 800 feet west of the greensboro,
from feet to 40 feet in ore of the best
quality found in the mine, paying as high
as $40 per ton.
The sulphurets are iron pyrites combined
with Il small percentage of arsenicol and
antimonial sulphurets, and have an assay
value of $40 per ton. The method of
saving the sulphurets is by IIendy concen-
traitors, rifles and blanket sluices, and the
gold is extracted therefrom at cost of $50
per ton to the company at the chlorination
and teaching works Of Barney x Noorhies,
Sutter Creek.
The mill is run by water power, contains
40 stamps of $50 pounds EACH with a drop
of to 81 inches, 96 times per minute,
crushing ,! tons to the stamp in "A hours.
The batteries are both high and low dis
charge, with No. s slot screens the apron
plates are 16xl4 inches, and sluice plates
IA inches wide The total length of the
plates for the 40 stamps is so feet, with an
inclination of 81 inches in 10 feet. The
amount of water used in 24 hours, in mill,
is l25 inches, with Il pressure of 234 feet.
Altitude of mine above sea-level, feet l.GOO
Number of stamps. ...................-..-.. 40